package string;

public class StringBuilderDemo {
    public static void main(String[] args) {
        String str="好好学习java";
        StringBuilder builder=new StringBuilder(str);
        builder.append("，就是为了找个好工作");
        System.out.println(builder);

        String line=builder.toString();
        System.out.println(line);

        builder.replace(4,8,"程序");
        System.out.println(builder);

        builder.delete(0,6);
        System.out.println(builder);

        builder.insert(0,"活着");
        System.out.println(builder);

        builder.reverse();
        System.out.println(builder);

        StringBuilder builder1=new StringBuilder("a");
        for (int i=0;i<10000000;i++){
            builder1.append("a");
        }
        System.out.println("执行完毕");
    }
}
